Wall-mounted electric heater



FIG. 1 is a front perspective view of the wall-mounted electric heater showing the design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The portions in broken lines in FIG. 3 form no part of the claimed design. 

CLAIM The ornamental design for the wall-mounted electric heater, as shown and described. 